Traditionally, baby feeders have taken the form of a generally cylindrical bottle (typically, glass or plastic) and a removable nipple closing one end of the bottle. The nipple is commonly secured to the bottle by a threaded circular ring or collar having a central hole through which the nipple protrudes and which holds it securely to the bottle. An example is U.S. Pat. No. 8,113,364, issued Feb. 14, 2012 to Ladan Asadi.
In some feeders using rings or collars to secure the nipple, flexible liners are inserted inside a rigid bottle to hold the liquid contents. An example is U.S. Pat. No. 6,616,000, issued Sep. 9, 2003 to Charles Renz and assigned to Playtex Products, Inc.
Some baby feeders attach a removable nipple directly to a disposable feeder body. An example is U.S. Patent Application Pub. No. 2012/0234790 A1.
Many kinds of flexible, reclosable bags are known and used for food storage, including liquid foods, and some of these are used for receiving storing breast milk. One example is the Medela™ “pump and save”™ breastmilk bag. This bag is essentially a flat pouch closed on three sides but having a throat or opening extending the width of the bag on the top side through which the bag may be filled when opened. The bag is closed by forcing a rib along the top into a corresponding channel to form a friction seal. A separate feeder bottle is required for subsequent feeding of the contents.
These systems all require significant handling during milk collection, storage, and preparation for feeding, and can unnecessarily expose the contents to contamination.